Method, Particle Sensor and Particle Sensor System for Measuring Particles

Abstract

A method and a particle sensor for measuring particles, especially soot particles, in which the particles to be detected accumulate in a measuring region of the particle sensor. The particles located in the gas stream or the particles already accumulated in the measuring region are burned by a combustion device, the combustion being controlled via a control signal from a control unit, which is electrically connected to a measuring device, in such a way that the quantity of the particles adhering in the measuring region remains constant. The physical variable of the combustion device, which leads to the controlled combustion of the particles, is drawn upon as the signal amplitude of the particle sensor.

Description

FIELD OF THE INVENTION [0001] The exemplary embodiment(s) and / or exemplary method(s) of the present invention relates to a method, a particle sensor and a particle sensor system for measuring particles, especially soot particles. BACKGROUND INFORMATION [0002] In order to measure particles, such as soot particles, in the exhaust gas of internal combustion engines, a particle sensor having a device for the detection of soot particles may be mounted in the exhaust pipe. [0003] A sensor is discussed in German patent document no. DE 101 33 384 A1 which is made up of two base (substrate) elements, the base elements having interdigital electrodes and an integrated heater, and being laminated to each other. The interdigital electrodes are used for measuring soot particles, the measurement being based on a resistive measuring principle: An accumulation of particles on the electrode structure leads to a conductivity change or impedance change of the area between the combs of the electrode. Fr...

AI Technical Summary

Benefits of technology

[0005] The exemplary method according to the present invention for measuring particles in a gas stream, especially soot particles, has the advantage that a signal amplitude is generated at least approximately continuously. Insensitive phases with respect to particle concentration during the detection of particles do not occur any more.

[0007] The sensor according to the present Application demonstrates a very compact construction, so that its use is made possible not only in the exhaust branch of a motor vehicle but in all those places where monitoring soot concentration is necessary or desirable in a space saving way.

Problems solved by technology

Even after the regeneration, soot cannot immediately be accumulated again, for, because of thermal inertia, the sensor requires a certain time for the thermalization of the sensor element by the exhaust gas.

Since, during the regeneration phase and the subsequent cooling phase of the sensor, no soot is able to be accumulated, during these phases the sensor is insensitive with respect to a possibly present soot concentration.

Images